Planting trencher



Dec. 10, 1957 J, a, HANSON 2,815,725

PLANTING mums Filed May 14, 1956 :s Sheets-Sheet 1 V INVENTOR JOHN G. HANSON ATTORNEYS Dec. 10, 1957 J. c. HANSON PLANTING TRENCI-IER 3 Sheets-Sheet 2 Filec} lay 14. 1956 INVENTOR JOHN C. HANSON ATTORNEYS Dec. 10, 1957 J. C.-HANSON 2,815,725

PLANTING TRENCl-IER 7 Filed May 14, 1956 3 Sheets-Sheet 3 Ground line 35 55 35 3 woose Sell 3 INVENTOR JOHN C. HANSON 0 W ATTORNEYS PLANTING TRENCHER John C. Hanson, Manistique, Mich., assignor to the United States of America as represented by the Secretary of Agriculture Application May 14, 1956, Serial No. 584,869

4 Claims. (Cl. 111--2) (Granted under Title 35, U. S. Code (1952), sec. 266) A non-exclusive, irrevocable, royalty-free license in the invention herein described, for all governmental purposes, throughout the world, with the power to grant sublicenses for such purposes, is hereby granted to the Government of the United States of America.

This invention relates to a device for planting seedlings. More particularly, it relates to attachments for a tractor-drawn plow which cut a trench of such shape that the roots of the seedling hang down to the proper depth and which automatically close the trench after the seedling has been planted.

Present planting machines all work by loosening or squeezing back soil on both sides of the trencher and depend on the skill and ability of the operator to get roots hanging straight down and to the proper depth. According to this invention, as will be described in greater detail below, there is produced a trench having one straight vertical wall with a square top edge and one overhanging or falling wall, thus permitting the seedling to the placed upright against the vertical wall and insuring that the falling soil, as it falls back to fill the trench will pull the roots straight downward.

In order that the invention may be fully understood, reference is made to the following description and to the accompanying drawings in which:

Figure l is a side elevation showing the trenching device attached to a plow in operating position with parts broken away;

Figure 2 is a plan view of the assembly shown in Figure 1 showing the relative location of the packing wheels and the trencher;

Figure 3 is a rear elevation of the trencher attached to a plow in its operating position with parts broken away;

Figure 4 is a perspective view from the rear showing the compartment for storing seedlings and the means for forming the square compacted corners and vertical wall on one side of the trench;

Figure 5 is a side elevation of the trenching blade itself showing details of the various surfaces and edges which cooperate to give the results of this invention;

Figure 6 is a rear view of the trenching blade showing additional details of the surfaces and edges;

Figure 7 is a bottom view of trenching blade showing still additional details of the surfaces and edges;

Figure 8 is a series of soil profiles showing the shape of the cross-section of the trench at progresive stages as the blade advance through the soil; and

Figure 9 is a view taken on line 9-9 of Figure 1 showing the construction and shape of means provided to guide the plow over roots and other obstacles, as will be described in greater detail below.

The essence of the present invention is in the shape of the novel trenching blade 1. As shown in Figures 5, 6, and 7, this blade possesses a pair of obverse parallel faces 2 and 3 separated by a relatively small thickness in comparison with its overall dimensions. The blade further has generally straight and bottom edges 4 and 5,

Z,8l5,?25 Patented Dec. 10, 1957 respectively, a leading edge 6, and a trailing edge 7. Leading edge 6 starts at a point on bottom edge 5 and extends upward and forward until it intersects curved edge 8. Near the intersection of edges 5 and 6, on face 2, there is provided an abrupt shoulder 9 extending substantially at right angles from the face of the blade. This shoulder extends upward and backward in a curve with its concave side forward. The lower end of the shoulder is provided with a slightly wider portion, or extension, 10 whose leading edge is swept backward, as shown in Figure 7. Shoulder 9 gradually decreases in width as it extends backward until it intersects and disappears in face 2 at a point 11. Beginning at a point near the lower extremity of shoulder 9, there is provided a rearward extending face 12 parallel to face 2. An inclined face 13 connects parallel faces 2 and 12 along parallel lines 14 and 15, respectively. Shoulder 9, for that portion of it which is coextensive with face 13, is rounded, and intersects face 13 tangentially. As will be readily apparent, face 12 is farther from obverse face 3 than face 2 is, with the result that the rear of trenching blade 1 is thicker than the forward part. This added width is used to provide a rearward opening slot 16 which forms part of a chute through which the seedlings are dropped into the open trench, as will be described in greater detail below.

My novel blade is advantageously used in conjunction with a short plow so that the entire assembly will have a short turning radius and thus permit planting in areas covered with tree stumps or other impediments. It will be obvious, however, that my novel trenching blade can be used in conjunction with any plow.

In a preferred form, the plow is somewhat modified to increase its efficiency of operation under the conditions usually encountered. Thus, as shown in Figure l-4, the trenching blade 1 is rigidly secured, as by means of bolts 17, 18, and 19, to one side of plate 20 which is itself rigidly secured to plow beam 21 by means of bolts 22, 23, and 24. Access to these bolts, which are inside hollow beam 21, is had through holes 25, 26, 27, 28, 29, and 30 in the sides of the beam. The conventional coulter is replaced by member 31 which is secured by one of its ends to the end of beam 21 and by its other to share 32 of moldboard 33. As shown in Figure 9, member 31 consists of T-section whose flat leading face 34 tapers to a point at its junction with share 32. The new member 31 which replaces the original coulter is provided to guide the planter over logs, roots, and other obstacles. The plow is preferably adjusted so that share 32 operates at a small depth beneath the original ground line 35 so as to effectively skim off and remove surface vegetation. As a further means for removing vegetation growing on the sides of the trench there are provided turf knives 36 and 37. One knife is on each side of the plow.

On the side of plate 20 opposite trenching blade 1, there is provided horizontal foot plate 38 which is rigidly secured, as by welding, to both blade 1 and vertical plate 39. Plate 39 is coextensive with slot 16, and together with it forms the other wall of the chute through which seedlings are dropped into the trench. Foot plate 33 serves to compact the soil on one side of the trench, and together with plate 39 forms a square corner of constant elevation at which to plant the trees. Foot plate 33 also serves as a foot rest for the operator. A number of vertical walls 40, 41, and 42 are also rigidly secured to foot plate 38, and with plate 20 form a compartment for holding the seedlings to be planted. Plate 46) also serves as a shield to protect the right hand and foot of the operator from large roots which spring back after being pried up by the moldboard. A pin 43 is provided on foot plate 38 to guide the roots of the seedling into alignment with the trench.

On the same side of plate 20 as trenching blade 1, a bracket 44 is secured to plate 20 by means of bolts 45 and 46. A third bolt 47 serves as a pivot for sleeve bearing 48 to which is secured a rearward extending beam 49. At the end of beam 49 there is mounted a pair of compacting wheels 50 and 51 and a seat for use of the operator while planting the trees. The two wheels 50 and 51 are not mounted on the same axle, as seen from Figures 1 and 2; and both wheels are entirely on one side of the trench, i. e., the side of the trench having the overhanging side wall made by abrupt shoulder 9 of the trenching blade. The reasons for this location will be apparent from the explanations below.

As stated above, the plow operates at such a depth below original ground line 35 that a thin layer of soil and vegetation are removed. As the plow progresses, foot plate 38, which is to one side of the narrow trench 53 cut by blade 1, compacts the soil on one side of the trench, thereby producing a shallow trough parallel to the former. Foot plate 38 is provided at its leading end with an upturned edge 54 to enable it to slide over obstacles. Vertical plate 39, together with plate 38 produces a vertical wall on one side of the trench so that the planted trees will be supported upright with the roots straight down.

Figure 8 shOWs the profiles of the trench at various points along the contour of blade 1. As the trencher advances, a narrow slit of progressively increasing depth is cut in the soil, as shown at forward sections A and B of Figure 8. The soil on the left side of the trench begins to rise as soon as the forward sections cut into the ground. Extension 10 at the lower end of the abrupt shoulder adds to this initial lifting or breaking upward, as shown at C in Figure 8. This initial breaking upward establishes the cleavage between the compact and loose soils, as shown by the inclined dotted line in profiles A to I, so that further opening of the trench, as in profiles D and E does not result in a horizontal squeezing of the soil beyond this cleavage, but rather in a further raising or climbing of the soil along sloping face 13 of the trenching blade to produce an overhanging wall of loose soil. The term cleavage, as used here denotes the plane of transition from loose to compact soil which is not a true cleavage or abrupt break along a plane. The soil removed in this manner on the left side of the trench is kept close to the area of operation and is readily available for dropping back once the tree has been planted.

The tree is dropped into the trench at F in Figure 8, and the loose soil of the overhanging wall then falls back into the trench to fill it. As shown in Figures 1, 2 and 8, the outside wheel 51 is in front of wheel 50. This causes the initial compacting of the soil to begin at a point remote from the trench wall and proceed toward the latter as wheel 50 moves up and complete the compacting close to the tree. In this manner, the movement of soil is in a downward direction, as shown in profiles G, H, and I of Figure 8, with the result that the roots are drawn straight downward for proper planting.

Projection 10 on the abrupt shoulder is of sufiicient width so that the width of loose soil area, L-L, as illustrated in profile C of Figure 8, is sufiicient to extend beyond forward compacting wheel 51. This is necessary to insure that wheel 51 does not ride on compact soil.

In order that the trench cut by the blade is of uniform depth the rounded portion 8 of leading edge 6 has been provided, as described above. As the trencher progresses, the leading edge must force grass, herbaceous roots, and tree roots downward against compact soil where they will be cut off, broken, or pass completely under the vtrencher. When these obstacles fail to do this, they tend to accumulate on the leading edge where they form a mass which raises the machine partly out of the ground.

Thus, it is important that the leading edge be swept back sufficiently. For the same reasons, the leading edge of projection 10 is swept back, as shown in Figure 7.

The machine may be drawn by any suitable means, such as a tractor, with care being taken that hitch fits snugly with no slap or play.

I claim:

1. A trencher for digging a trench having a vertical wall of compact soil on one side of said trench and an overhanging wall of loose soil on the other side of said trench, said trencher comprising a blade member having a pair of parallel obverse faces and top, bottom, leading, and trailing edges, said trailing edges being provided with a rearward opening vertical slot, said obverse faces being separated by a relatively small thickness in comparison with the height and length, said leading edge commencing at a point on the bottom edge and extending upward and forward therefrom, an abrupt shoulder having a sharp leading edge extending substantially normally from a first of said obverse faces, said shoulder commencing with its leading edge at a point near the intersection of the leading edge of the blade and the bottom edge of the blade and extending upward and rearward in a curve, said shoulder progressively decreasing in width from its leading edge until it intersects and vanishes in said first obverse face at a point near the top and trailing edges thereof, said shoulder being adapted to produce a loose overhanging wall of soil on one side of the trench; a face parallel to said first obverse face commencing at a point near the bottom of said abrupt shoulder and extending rearward, and an inclined face connecting said first obverse face and said face parallel to said first obverse face.

2. In a trencher for digging a trench having a vertical wall of compact soil on one side of said trench and an overhanging wall of loose soil on the other side of said trench, said trencher comprising: a supporting member; a blade member rigidly supported beneath said supporting member adapted to be drawn beneath the surface of the soil to dig a trench; and means for compacting loose soil raised from the trench; said blade member having a pair of parallel obverse faces and top, bottom, leading, and trailing edges, said obverse faces being separated by a relatively small thickness in comparison with the height and length, said leading edge commencing at a point on the bottom edge and extending upward and forward therefrom, an abrupt shoulder adapted to produce an overhanging wall of loose soil on one side of the trench having a sharp leading edge extending substantially normally from a first of said obverse faces, said shoulder commencing with its leading edge at a point near the intersection of the leading edge of the blade and the bottom edge of the blade and extending upward and rearward in a curve, said shoulder progressively decreasing in width from its leading edge until it intersects and vanishes in said first obverse face at a point near the top and trailing edges thereof, a face parallel to said first obverse face commencing at a point near the bottom of said abrupt shoulder and extending rearward, an inclined face connecting said first obverse face and said face parallel to said first obverse face.

3. In a trencher for digging a trench adapted to receive seedlings for planting, said trench having a vertical wall of compact soil on one side and an overhanging wall of loose soil on the other side, said trenchcr comprising an elongated supporting member having a forward and rear end, a blade member rigidly supported beneath said supporting member adapted to be drawn beneath the surface of the soil to dig a trench, and means behind the blade for compacting loose soil raised from the trench, the improvement which comprises: cutting means rigidly secured to said supporting member near its forward end adapted to remove a thin layer of soil and vegetation along a longitudinal path of travel; an improved blade member to the rear of said cutting means, said blade memher having a pair of parallel obverse faces and top, bottom, leading, and trailing edges, said trailing edges being provided with a rearward opening vertical slot, said ohverse faces being separated by a relatively small thickness in comparison with the height and length, said leading edge commencing at a point on the bottom edge and extending upward and forward therefrom, an abrupt shoulder adapted to produce a loose overhanging wall of soil on one side of the trench, said shoulder having a sharp leading edge extending substantially normally from a first of said obverse faces, said shoulder commencing with its leading edge at a point near the intersection of the leading edge of the blade and the bottom edge of the blade and extending upward and rearward in a curve, said shoulder progressively decreasing in width from its leading edge until it intersects and vanishes in said first obverse face at a point near the top and trailing edges thereof, a face parallel to said first obverse face commencing at a point near the bottom of said abrupt shoulder and extending rearward, and an inclined face connecting said first obverse face and said face parallel to said first obverse face; and means to one side of the second obverse face, and separated therefrom, for compacting the soil in the other wall of the trench.

4. A machine for digging a trench adapted to receive seedlings for planting, said trench having a vertical wall of compact soil on one side and an overhanging wall of loose soil on the other side, said machine comprising a blade member adapted to be drawn beneath the surface of the soil having a pair of parallel obverse faces and top, bottom, leading, and trailing edges, said trailing edges being provided with a rearward opening vertical slot, said obverse faces being separated by a relatively small thickness in comparison with the height and length, said leading edge commencing at a point on the bottom edge and extending upward and forward therefrom, an abrupt shoulder adapted to produce an overhanging wall of loose soil on one side of the trench, said shoulder having a sharp leading edge extending substantially normally from a first of said obverse faces, said shoulder commencing with its leading edge at a point near the intersection of the leading edge of the blade and the bottom edge of the blade and extending upward and rearward in a curve, said shoulder progressively decreasing in width from its leading edge until it intersects and vanishes in said first obverse face at a point near the top and trailing edges thereof, a face parallel to said first obverse face commencing at a point near the bottom of said abrupt shoulder and extend ing rearward, and an inclined face connecting said first obverse face and said face parallel to said first obverse face; a first plate to one side of the second obverse face separated therefrom and substantially coextensive therewith forming, in conjunction with the aforementioned vertical slot, a passageway for dropping seedlings into the trench; and a second plate rigidly secured to said first plate extending normally therefrom away from said second obverse face, said second plate being at such a height that it isin contact with the horizontal surface of the soil, said first and second plates together compacting the coil of one vertical wall of the trench and the horizontal surface on the same side, respectively.

References Cited in the file of this patent UNITED STATES PATENTS 1,972,281 Walling Sept. 4, 1934 2,431,731 Campbell Dec. 2, 1947 FOREIGN PATENTS 651,965 Germany Oct. 22, 1937 563,515 Great Britain Aug. 17, 1944 OTHER REFERENCES Agricultural Engineering, vol. 28, September 1947, pages 387-390 and 396. The Fundamentals of Me chanical Tree Planter Design and Performance. Copy in Scientific Library and Division 1. 

